SOME WOOD-BORING INSECTS 391 



the tappings most carefully say that the tickings are 

 answered regularly, in the pauses, by a beetle in another 

 location. The beetles and their noises have been subjects 

 of investigation by several observers from early times. In 

 1867 Smith found it easy to induce some beetles that he 

 had in captivity to beat whenever he wished. He simply 

 tapped four or five times with a lead pencil upon the table 

 near the box in which the insects were confined. He 

 described their habits as follows : " Raising themselves 

 on their anterior legs, they commenced bobbing their 

 heads up and down rapidly, tapping with their mandibles 

 on the bottom of the box. This performance I could 

 elicit almost at pleasure : the number of taps varied from 

 four to five — usually five are given. The insects have 

 kept on repeating their love-call at intervals throughout 

 the day. I fancy they are a couple of males. After 

 inciting them to tap once or twice they become restless, 

 and run about the box, occasionally stopping as if listening 

 for a repetition of the sound : a few taps with the pencil 

 sets them off again." 



A later investigator, Morley, made some careful ob- 

 servations on the ticking of Anobium. He found that 

 more than five ticks were made at a time. He was unable 

 to count them, but estimated them at thirty or forty. 



The foregoing beetle is not alone responsible for the 

 tappings we sometimes hear in old timbers. A closely 

 related species, Anobium domesticum, also ticks and has 

 probably often been the cause of alarm to superstitious 

 people. 



In conclusion, it should be noted that these Anobium 

 beetles are also injurious to books. This is notably true 

 of Anobium hirtum, a native of southern Europe but now 



